As a preform for manufacturing of saw blades respectively saw bands with hard and wear-resistant regions of the tip of the teeth a composite steel blade or a composite steel band (bimetal band) is generally used. A strip of a cutting material is welded or braised to the edge of a tough, elastic carrier band made of steel.
Since this preform consists of different materials it is also known under the name bimetal band or bimetal blade. Because of the usage of for example tool steel respectively other cutting materials the later regions of the tip of the teeth of the thereof manufactured saw blades respectively saw bands comprise a higher wear resistance and the saw blade or band reaches a higher lift time.
For the manufacturing of the saw blade or band a tooth profile respectively a tooth contour is cut out of the above mentioned bimetal band corresponding to the later saw band or blade. The in this way manufactured tip areas comprise peak areas consisting of tool steel, whereas the rest of the saw blades consist of tough elastic steel of the carrier band. The above described cutting of the cutting contour is related to a high lost of expensive cutting material because the material of the cut space between the teeth is lost.
Therefore in EP 1 616 651 A1 a preform for manufacturing of saw blades or bands is proposed in which a band of a cutting material is welded between the edges of two carrier bands. Thereby two saw blades or bands can be manufactured out of one pre-form respectively, by separating the preform through the segments along the later cutting contour.
The segments of EP 1 616 651 A1 are to be fixed by welding, braising or by other suitable fixing or connecting methods to the carrier bands. The connection of the segments to the carrier bands is carried out by continuous welds or brazing joints along the edges of the segments.
Therefore the present invention has the technical problem to provide a method for manufacturing a preform for saw blades respectively saw bands which can be carried out easily. Furthermore the manufacturing method should guarantee continuously high quality of the preforms. Finally the manufacturing process should be able to be automated to provide a especially cost effective preform.